- Overview
- RADIUS Accounting Log
- Using WiMAX in Cisco Prime Access Registrar
- Replication Log
- Using On-Demand Address Pools
- Wireless Support
- Enforcement of Licensing Models
- Logging Syslog Messages
- Troubleshooting Cisco Prime Access Registrar
- Cisco Prime Access Registrar Tcl, REX, and Java Dictionaries
- Environment Dictionary
- RADIUS Attributes
- Support for REST API in Cisco Prime Access Registrar
- Supported Counters and Error Statistics
- Health Monitoring in Cisco Prime Access Registrar
Troubleshooting Cisco Prime Access Registrar
This chapter provides information about techniques used when troubleshooting Cisco Access Registrar (Prime Access Registrar) and highlights common problems.
Gathering Basic Information
Table 9-1 lists UNIX commands that provide basic and essential information to help you understand the Prime Access Registrar installation environment.
Note More information about these commands and their options is available using the man command in a terminal window on the Sun workstation.
Troubleshooting Quick Checks
Many of the most common problems can be diagnosed by doing the following:
Disk Space
Running out of disk space can cause a number of problems including:
- Failure to process RADIUS requests
- Parts of the Prime Access Registrar configuration disappearing in aregcmd
- Failure to log into aregcmd
Check that the Prime Access Registrar installation partition ($INSTALL) and /tmp are not at capacity.
Resource Conflicts
Resource conflicts are a common reason for the Cisco Prime Access Registrar server failing to start. The most common resource conflicts are the following:
No Co-Existence With Cisco Network Registrar
Cisco Network Registrar cannot coexist on a machine running Prime Access Registrar for this reason. You can determine if CNR is running by entering the following command line in a terminal window:
Port Conflicts
The default ports used by the Prime Access Registrar server are ports 1812 and 1813. You should check to determine that no other applications are listening on the same ports as Prime Access Registrar.
You can check to see which TCP ports are in use by entering the following command line:
You can check to see which UDP ports are in use by entering the following command line:
Note If you configure the Prime Access Registrar server to use ports other than the default, you will have to specifically add those ports if you want to use them.
Cisco Prime Access Registrar Log Files
Examining the Prime Access Registrar log files can help you diagnose most Prime Access Registrar issues. By default, the Prime Access Registrar log files are located in /opt/CSCOar /logs. Table 9-2 lists the Prime Access Registrar log files and the information stored in each log.
Modifying File Sizes for Agent Server and MCD Server Logs
The two parameters added to the car.conf file under $BASEDIR/conf affect the agent_server_logs and config_mcd_server_logs logs files:
You will find these new parameters at the beginning of the car.conf file. When the log file size reaches the value set in AGENT_SERVER_LOG_SIZE, a rollover of the agent_server_log_file occurs. The value set in AGENT_SERVER_LOG_FILES specifies the number of log files to be created.
Using xtail to Monitor Log File Activity
A useful way of monitoring all of the log files is to run xtail, a utility provided with Prime Access Registrar. The xtail program monitors one or more files and displays all data written to a file since command invocation.
Run xtail in a dedicated terminal window. It is very useful for monitoring multiple logfiles simultaneously, such as with a command line like the following:
Note Cisco AR 4.1.5 and later include the millisecond field in the logs’ timestamp.
Modifying the Trace Level
By modifying the trace level, you can gather more detailed information in the log files about what is happening in the Prime Access Registrar server. There are five different trace levels. Each higher trace level also includes the information logged using lower trace levels. The different trace levels provide the following information:
- Level 0—No tracing occurs
- Level 1—Indicates when a packet is sent or received and when a status change occurs in a remote server (RADIUS Proxy and LDAP)
- Level 2—Information includes the following:
– Which services and session managers are used to process
– Which client and vendor objects are being used to process a packet
– More details about remote servers (RADIUS Proxy and LDAP), packet transmission, and timeouts
– Details about poorly-formed packets.
– Tracing of errors in Tcl scripts when referencing invalid RADIUS attributes
– Details about local userlist processing
– Advanced duplication detection processing
Installation and Server Process Start-up
The installation process installs the Prime Access Registrar software to the specified installation directory and then starts the server processes. This process rarely fails but the following checks should always be performed:
- Ensure that there is an installation success message at the end of the pkgadd dialog, otherwise check the dialog for the problem
- Follow the installation instructions carefully especially when performing an upgrade. For example, when upgrading to 1.6R1, 1.6R2, or 1.6R3, a post-installation upgrade script needs to be run
- Pay attention to the information included in README files
At the end of a successful installation, arstatus should show the following four server processes:
If any of the above processes are not displayed, check the log file of the failed process to determine the reason. The MCD processes might fail to start if Cisco Network Registrar is installed on the same machine.
The manual method of starting and stopping the Prime Access Registrar processes is using the arserver utility.
To start Prime Access Registrar processes: arserver start
To stop Prime Access Registrar processes: arserver stop
To restart Prime Access Registrar processes: arserver restart
aregcmd and Cisco Prime Access Registrar Configuration
While troubleshooting, you should always use the aregcmd command trace to turn on tracing. With tracing active, Prime Access Registrar generates debugging output to the log file name_radius_1_trace.The syntax is:
When you do not specify a server, Prime Access Registrar sets the trace level for all servers in the current cluster. When you do not specify a trace level, the currently set level is used. The default trace level is 0.
Running and Stopped States
Prime Access Registrar can be in two states, running or stopped. In either state, all four Prime Access Registrar processes remain running. The state of Prime Access Registrar will be displayed when logging into aregcmd or by using the aregcmd status command:
The start and stop commands allow Prime Access Registrar to move between states. Reload is equivalent to a stop followed by a start if Prime Access Registrar is already running, and just a start if it is already stopped.
During the transition from running to stopped, Prime Access Registrar stops processing new RADIUS requests and releases resources such memory, network and database connections and open files.
During the transition from stopped to running, Prime Access Registrar reverses this process by opening a connection with its internal database, reading configuration data, claiming memory, establishing network connections, opening files, and initializing scripts. During this transition, problems can occur. Prime Access Registrar might fail to start and display the following:
Prime Access Registrar failed to move from stopped state to running:
This might occur for a number of reasons including the following:
- An invalid configuration
- Insufficient memory
- Listening ports already in use by another application
- Unable to open files
- Unable to initialize scripts
Check the name_radius_1_log file for the one of these indications.
RADIUS Request Processing
The main technique for troubleshooting RADIUS request processing in Prime Access Registrar is to examine the name_radius_1_trace log file with the trace level set to 5. Most issues are fairly self-explanatory. Some issues that can arise are as follows:
- Prime Access Registrar has marked a remote server as down
- A resource manager has run out of resources (for example, user or group session limit has been reached or no more IP addresses are available)
- A configuration error (such as an accounting service not being set)
- A run time error in a script
Some issues are not immediately evident from the log files though, such as the following:
Other Troubleshooting Techniques and Resources
aregcmd Stats Command
The aregcmd command stats provides statistics on request processing.
Core Files
A core file in the Prime Access Registrar installation directory is an indication that Prime Access Registrar has crashed and restarted. Check that the radius server process generated the core file using the UNIX file command:
Check the timestamp on the core file and look for corresponding log messages in the name_radius_1_log file in $INSTALL/logs. The word assertion commonly appears in core messages. Try to establish what caused the problem and contact Cisco TAC.
radclient
The Prime Access Registrar package provides a utility called radclient that allows RADIUS requests to be generated. Use radclient to test configurations and troubleshoot problems.
Cisco Prime Access Registrar Replication
For more information about using Prime Access Registrar replication, see Chapter4, “Replication Log”
Checking Prime Access Registrar Server Health Status
To check the server’s health, use the aregcmd command status. The following issues decrement the server’s health:
Note One of the parameters in the calculation of the Prime Access Registrar server’s health is the percentage of responses to Access-Accepts that are rejections. In a healthy environment, the rejection percentage will be fairly low. An extremely high percentage of rejections could be an indication of a Denial of Service attack.
- Configuration errors
- Running out of memory
- Errors reading from the network
- Dropping packets that cannot be read (because the server ran out of memory)
- Errors writing to the network.
Prime Access Registrar logs all of these conditions. Sending multiple successful responses to any packet, increments the server’s health.